Perfluoro alkyl sulfonamides useful as water and oil repellency agents

ABSTRACT

Segmented fluorocarbon sulfonic acids comprising the reaction product of a perfluoroalkyl-alkyl halide and a sulfonation reagent as well as the acid anhydrides, metal salts, sulfonyl halides and sulfonamides thereof. The resulting compositions possess unique surface active properties and thus are applicable as effective emulsifying agents. They may also be used as intermediates in the preparation of water and oil repellency agents.

United States Patent [191 Ray-Chaudhuri et al.

[ Nov. 4, 1975 PERFLUORO ALKYL SULFONAMIDES USEFUL AS WATER AND OILREPELLENCY AGENTS [75] Inventors: Dilip K. Ray-Chaudhuri, Somerville;

Carmine P. Iovine, Somerset, both of NJ.

[73] Assignee: National Starch and Chemical Corporation, Bridgewater,NJ.

[22] Filed: Nov. 12, 1973 [21] Appl. No.: 414,870

Related US. Application Data [60] Division of Ser. No. 278,957, Aug. 9,1972, Pat. No. 3,810,939, which is a continuation-in-part of Ser. No.18,720, March 11, 1970, abandoned, which is a continuation-in-part ofSer. No. 755,814, Aug. 28, 1968, abandoned.

[52] US. Cl. 260/556 F; 260/513 R; 260/543 R [51] Int. Cl. C07C 143/72[58] Field of Search 260/556 F [56] References Cited UNITED STATESPATENTS 3,829,466 8/1974 Staffe et al. 260/556 F X 3,864,396 2/1975Staffe et al. 260/556 F FOREIGN PATENTS OR APPLICATIONS 2,002,460 7/1970Germany 260/556 F Primary ExaminerDaniel E. Wyman AssistantExaminer-Thomas A. Waltz Attorney, Agent, or Firm--Thomas B. Graham 57ABSTRACT 6 Claims, No Drawings PERFLUORO ALKYL SUIQFONAMIDES USEFUL ASWATER AND OIL REPELLENCY AGENTS RELATED APPLICATIONS This application isa division of our copending application Ser. No. 278,957 filed Aug. 9,1972, now U.S. Pat. No. 3,810,939 which, in turn, is acontinuation-inpart of Ser. No; 18,720 filed Mar. 11, 1970, nowabandoned, which, in turn, was a continuation-impart of Ser. No. 755,814filed Aug. 28, 1968, now abandoned, and assigned to the assignee of theinstant application.

SUMMARY OF THE INVENTION It is the object of this invention to preparenovel segmented fluorocarbon sulfonic acids and various derivativesthereof. Other objects and advantages of this invention will becomeapparent to the practitioner from the following description.

Thus, the compositions of this invention comprise the novel segmentedfluorocarbon sulfonic acids corresponding to the formula wherein Z is aradical containing from 3 to 20 carbon atoms inclusive and is 7 selectedfrom the group consisting of straight and branched chain perfluoro alkylradicals, and- Y is a radical selected from the group consisting ofalkylene, alken'yle'ne,"cyclo alkylene, bridged cyclo alkylene andar-arkylene radicals.

Also included within the scope of this invention are the derivatives ofthe specified fluorocarbon sulfonic acids including'for example, i

a. anhydrides of these acidscorresponding to the formula (Z Y SO O;

b. metal and ammonium salts of these acids corresponding to theformula(Z Y SO M wherein M is a metal atom oran ammonium group and a is thenumber of sulfonyl groups coordinated with said metal or'ammonium groupand, correspondingly, the valence of said metal or ammonium group;

c. sulfonyl halides of these acids;corresponding to the formula Z Y SO Xwherein X is a halogen atom selected from the group consisting ofchlorine, bromine, and iodine atoms; and;

d. sulfonamides of these acids corresponding to the formula Z Y SO, NRwherein R is selected from the group consisting of hydrogen atoms andalkyl radicals; the Z and Y components of these derivatives being aspreviously described.

It will thus be seen that the novel sulfonic acid materials of thisinvention are basically four component compositions whereinthefluorocarbon group (Z) is linked to the sulfur atom ofthesulfonylgroup via a hydrocarbon radical (Y), herein, referred to as thesegmented group, and, the sulfur atom is linked, in turn, to eithera'hydroxyl group (acids), an oxygen atom (anhydrides), a metal atom(salts), a halogen atom (sulfonyl halides) or, a nitrogen atom(sulfonamides).

DESCRIPTION OF THE PREFERRED EMBODIMENT In brief, the procedure forpreparing the novel composition of this invention ordinarily comprisesreacting:

'l. a perfluoroalkyl-alkyl halide with 2. a sulfonation reagent; andthereafter, if desired,

derivatizing the reaction product to any corresponding form.

However, perfluoroalkyl olefins and perfluoro alkyl substituted aromatichydrocarbons can also be used in place of the perfluoroalkyl-alkylhalide.

The perfluoroalkyl-alkyl halides applicable for use in the preparationof the novel compositions of this invention correspond to the formula[ZYW] wherein Z and Y are as previously described and W is a halogenatom selected from the group consisting of chlorine, bromine and iodineatoms.

Thus, among the applicable perfluoroalkyl-alkyl halides are included:l-iodo-2-perfluoroheptyl-ethane, i.e. c,F,,cH,cH,1;1-iodo-4-perfluoropropyl-n-butane, i.e. C F-,(CH I; l-bromo-ll-perfluoroheptyl-nundecane, i.e. C F, (C1-1,),,Br; 2-perfluoroheptyl-5-bromomethybnorbornane; 1-iodo-4-perfluoroheptyl-2- butene, i.e. C,F CHCH=CHCH I; l-bromo-l lperfluoroheptyl-lO-undecene, i.e. C-,FCI-1=CH(CI-I CI-1 Br; and, 1-iodo-2-perfluoropropyl-ethane, i.e. C FCI-1 CH L Methods for preparing these perfluoroalkyl-alkyl halides arewell known to those skilled in the art (see U.S. Pat. Nos. 2,965,659 and3,145,222). Typical preparative procedures include the addition reactionof perfluoroalkyl iodides and bromides with terminal olefins, and theaddition reaction of perfluorosulfonyl chlorides with terminal olefins.Where these procedures result in the preparation of secondary halides,such halides may be converted into the primary halide prior tosulfonation, or, may be sulfonated directly, as by means of theprocedures hereinafter described.

The sulfonation procedures which may be utilized to prepare the novelcompositions of this invention are also well known to those skilled inthe art. Among the sulfonation reagents that are used in theseprocedures are included alkali metal sulfites, alkali metal bisulfites,sulfuric acid, sulfur dioxide, sulfuryl chloride and chlorosulfonicacid. In a typical procedure, which is preferred for purposes of thisinvention because of its efficiency and economy, one mole of theperfluoroalkyl-alkyl halide is admixed with from about one to two molesof an alkali metal sulfite and, thereafter, heated to a temperature offrom about to 200C. for a period of about 1 to 30 hours. The reaction isconducted either in water or in a mixture of water and a water miscibleorganic solvent such, for example, as ethylalcohol, isopropyl alcohol,dimethyl formamide and dimethyl sulfoxide. The fluorocarbon sulfonicacid product is isolated as the alkali metal sulfonate which may,thereafter, be converted into the corresponding gas to produce thefluoroalkyl-alkyl sulfonyl chloride;

(2) the reaction procedure whereby the fluoroalkylalkyl halide is firstconverted. into the corresponding alcohol which, in turn, is reactedwith sulfuric acid in the presence of a neutralization agent, such assodium hydroxide, potassium hydroxide and sodium carbonate, to producethe fluoroalkyl-alkyl sulfate salt; the resulting salt then beingreacted with an alkali metal sulfite to produce the desiredfluoroalkyl-alkyl sodium sulfonate salt; (3) the reaction of thefluoroalkyl-alkyl halide with thiourea or an alkali metal thiocyanate toproduce respectively the S-alkyl isothiouronium hydrohalide salt orthiocyanate; these compounds can be converted directly into the sulfonylchloride by treatment with aqueous chlorine; and (4) the directsulfonation of a fluoroalkyl-alkyl substituted aromatic hydrocarbon withchlorosulfonic or sulfuric acid. Further information relating to theapplicable sulfonation reactions may be obtained by referring toSulfonation and Related Reactions, by E. E. Gilbert, published in 1965by Interscience Publishers, New York, New York.

Conversion of the novel compositions of this invention into thecorresponding acids, metal salts, anhydrides, sulfonyl halides andsulfonamides may be accomplished by means of well known derivatizationtechniques. Thus, the fluoroalkylalkyl sulfonic acids may be convertedinto metallic salts by reacting the acid with a metallic oxide,hydroxide, carbonate, etc., e.g. sodium carbonate, calcium oxide,potassium hydroxide, barium chloride and silver nitrate. The anhydridesof these acids may be prepared by heating the acid with a stoichiometricexcess of phosphorus pentachloride. The sulfonyl halides may be preparedby interaction of the acid with approximately an equimolar concentrationof a phosphorus halide such, for example, as phosphorus pentachloride.The resulting sulfonyl halides may, in turn, be reacted with liquidammonia, gaseous ammonia, ammonium carbonate or various amine compoundsin order to prepare the corresponding sulfonamides. Furthermore, where asulfonate salt is directly, prepared by the sulfonation reaction, it maybe converted into the acid form by means of a decomposition techniqueusing dry gaseous hydrogen chloride in an appropriate solvent.

it should be noted that the novel compositions of this invention may beutilized in preparing additional fluoroalkyl-alkyl derivatives such, forexample, as amine salts, sulfones sulfonic acid esters, substitutedsulfonamides and chloroamides.

As previously noted, these novel sulfonic acid compositions exhibitunique surface active properties. Thus, these materials are effective inreducing the surface tension properties of both aqueous and non-aqueoussystems. Their unique characteristics enable them to be used as wettingagents, surface tension reducing agents, foaming agents, anti-foamingagents, dispersing agents, emulsifying agents, emulsion and dispersionstabilizers, detergents, corrosion inhibitors and fluxes, etc.

Furthermore, polyvalent sulfonate salts, e.g. (C F CH CH SO ){Ca may beutilized to impart water and oil repellent properties to paper and paperproducts. Thus, such materials may be applied to paper from wateralcohol solutions by means of convenfrom all types of both cellulosicand combinations of cellulosic and non-cellulosic fibers. The cellulosefibers which may be used include bleached and unbleached sulfate(kraft), bleached and unbleached sulfite, bleached and unbleached soda,neutral sulfite, semichemical, chemi-groundwood, ground wood, and anycombination of these fibers. In addition, synthetic fibers of theviscose rayon or regenerated cellulose type as well as of the chemicallysynthesized type can also be used. It should be noted that as little asabout 0.1 percent of the repellent, based on the dry weight of the pulpin the finished sheet, is sufficient to provide effective water and oilrepellency.

The novel sulfonic acid compositions of this invention may also be usedas intermediates in the preparation of water and oil repellency agentswhich are applicable for use on a wide variety of substrates.

The following examples will further illustrate the embodiment of thisinvention. In these examples, all parts given are by weight, unlessotherwise noted.

EXAMPLE I This example illustrates the preparation of afluoroalkyl-alkyl sodium sulfonate salt by means of an aqueous sulfitereaction technique.

A pressurized reaction vessel was charged with 38 parts ofl-iodo-2-perfluoropropyl-ethane, 22 parts of anhydrous sodium sulfite,40 parts of water, and 30 parts of ethyl alcohol. The temperature of thereaction system, which was in emulsion form, was raised to l20-l25C.over a period of four hours and the reaction allowed to proceed at thistemperature and a pressure of psi for an additional 16 hours. Thereactor contents were then cooled and filtered.

Upon recrystallization of the solid product, a 76.5 percent yield ofsodium-( 2-perfluoropropyl)ethane sulfonate was recovered in the form ofwhite platelets which melted at a temperature in excess 250C. and whichexhibited slight solubility in both water and ethyl alcohol.

It should be noted that this reaction is suitable for preparing any ofthe sodium sulfonate reaction products in accordance with thisinvention. Thus, comparable sodium sulfonate salts may be produced byreplacing the above described fluoroalkyl-alkyl halide, in the reactionsystem, with any of the following fluoroalkylalkyl halides:

(a) l-iodo-4-perfluoropropyl-n-butane;

(b) l-iodo-l l-perfluoroheptyl-n-undecane;

(c) l-bromo-l l-perfluoroheptyl-n-undecane;

(d) 2-perfluoroheptyl-5-bromomethyl-norbomane; and

(e) l-iodo-4-perfluoroheptyl-2-butene.

EXAMPLE II This example illustrates the preparation of additionalfluoroalkyl-alkyl sodium sulfonate salts typical of the novel productsof this invention.

A number of different fluoroalkyl-alkyl sodium sulfonate salts wereprepared according to the general procedure set forth in Example I,hereinabove, utilizing a variety of reagents at different concentrationlevels under varying reaction conditions. These variables are describedin the following table.

TABLE Salt No parts No. No. No. No. No.

l-iodo-2-perfluoroheptyl-ethane 52.4 l iodo-4-perfluoroheptyl-n-butane15.0 l-bromo-l Lperfluoroheptyl-nudecane 17.0 l-bromo-ll-perfluoroheptyl-IO- undecene 23.02-perfluoroheptyl-5-bromo-methylnorbornane 14.0 anhydrous sodium sulfite19.0 4.1 8.5 5.8 3.8 water 45 4O 20 ethyl alcohol 35.0 15.8 31.6 27.017.0 reaction temperature (C.) 120 160-5 130 120 125 reaction time(hours) 21 6 21 18 18 85 56 69 56.3 18 product yield melting point (C.)240- 242- 218- 213- 296 EXAMPLE 111 This example illustrates a procedurefor converting a fluoroalkyl-alkyl sodium sulfonate salt into itscorresponding sulfonic acid.

A reaction vessel fitted with a gas inlet tube, a distillation apparatusand means for mechanical agitation was charged with parts of diethylether and 5 parts of sodium-(4-perfluoroheptyl) butane sulfonate; thelatter fluoroalkyl-alkyl sodium sulfonate salt having been preparedaccording to the procedure set forth in Example 11-2. The resultingsuspension was maintained at room temperature and subjected to vigorousagitation whereupon dry gaseous hydrogen chloride was passed through thesystem for a period of 3 hours.

Upon completion of the decomposition reaction, the ether was removedfrom the system and the resulting product was washed several times withportions of fresh ether in order to remove the residual hydrogenchloride. The crude sulfonic acid was then vacuum dried andrecrystallized from benzene thereby yielding a white crystallinefluoroalkyl-alkyl sulfonic acid which melted at l02106C. and which wassoluble in water.

EXAMPLE IV This example illustrate a procedure for converting afluoroalkyl-alkyl sodium sulfonate salt into its corresponding sulfonylchloride.

A reaction vessel fitted with a distillation apparatus and means formechanical agitation was charged with 20 parts ofsodium-(2-perfluoroheptyl)ethane sulfonate, which was prepared accordingto the general procedure set forth in Example 11-1, and 16.7 parts ofphosphorus pentachloride. An exothermic reaction occurred immediatelyand was accompanied by a brief period of phosphorus oxychloride reflux.Upon cessation of the exothermic reaction, the mixture was heated at50-60C. for a period of 2 hours.

Thereafter, the reaction mixture was poured over 500 parts of crackedice, thoroughly dispersed therein by means of vigorous agitation, andfiltered. This procedure was repeated several times until the filtrateexhibited a neutral pH. The product was then dried, dissolved in acetoneand filtered free of unconverted fluoroalkyl-alkyl sodium sulfonate.Upon removing the acetone, an 86 percent yield of the correspondingfluoroalkyl-alkyl sulfonyl chloride was recovered in the form of a whitesolid which melted at 39-42C. and

which was soluble. in heptane, benzene, ether and acetone.

EXAMPLE V This example illustrates a procedure for the conversion of afluoroalkyl-alkyl sulfonyl chloride into its corresponding sulfonamide.

A reaction vessel fitted with a gas inlet tube, a distillation apparatusand means for mechanical agitation was charged with 40 parts of benzeneand 13 parts of 2-perfluoroheptyl-ethane sulfonyl chloride, as preparedin Example IV. Anhydrous ammonia gas was then passed into the system ata rate which was sufficient to maintain the temperature of the systembetween 40C. and 50C. This procedure was continued for 30 minuteswhereupon the reaction product was filtered and washed with water toremove the residual ammonium chloride. The product was then dried andrecrystallized from water thereby producing an percent yield of a whitesolid fluoroalkyl-alkyl sulfonamide which melted at 98-.l04C.

, EXAMPLE VI This example illustrates the preparation of an aromaticfiuoroalkyl-alkyl sulfonic acid derivative.

A reaction vessel fitted with a reflux condenser, slow addition funnel,moisture trap, thermometer and means for mechanical agitation wascharged with 9.3 parts of chlorosulfonic acid to which was added over aperiod of 60 minutes, 13 parts of 1-phenyl-3-perfluoroheptyln-propane.The reaction was exothermic, and the addition rate was so regulated thatthe reaction temperature did not exceed 35C. After the addition wascompleted, the reaction mixture was stirred for an additional period of1 hour at room temperature, and thereafter the mixture was slowly pouredover cracked ice. The fluorocarbon product was collected and dissolvedin diethyl ether. The ether solution was washed with water until thewash water was neutral to litmus and dried over sodium sulfate. Uponremoving the solvent, the sulfonyl halidep-(1H,l1-1,2I-l,21-1,3H,3l-l-perfluorodecyl) benzene sulfonyl chloride,was obtained in the form of a viscous yellow oil (13 parts or 84% yield)and was thereafter converted into the corresponding sulfonamide whichmelted at l0l-l06C.

EXAMPLE vn This example illustrates the preparation ofl-bromoll-perf1uoroheptyl-n-undecane which was used as the startingmaterial for a compound illustrated in Example II.

Part A:

A reaction vessel as used in the previous examples was charged with 0.15gm of a, a azobisisobutyronitrile, 49.6 gm (0.1 mole) perfluoroheptyliodide and 21.6 gm (0.102 mole) undec-lO-enyl acetate. The reactionmixture was vacuum degassed using conventional freeze thaw techniquesand left under positive nitrogen pressure. The mixture was thereafterheated to 85-90C. and an additional 0.15 gm of azobisisobutyronitrile inml of tbutanol was slow added over a period of 3 hours. Residual C F, Iwas removed on completion of the heating period to yield crude ll-perfluoroheptyl-lO-iodo-undecyl-l-acetate. The conversion was found tobe 91%.

Part B:

A reaction vessel as used in the previous examples was charged with 30gm of the product of Part A, 100 ml of anhydrous ethanol and 4 gm ofgranular zinc. The mixture was saturated with dry hydrogen chloride andthereafter heated to 75C. After heating for 1 hour at 75C. an additional4 gm of zinc was added to the reaction mixture and heating was continuedfor 5 hours. The mixture was periodically resaturated with dry hydrogenchloride so that an excess of hydrogen chloride was present throught theentire heating period.

At the completion of the heating period, the hot reaction mixture wasfiltered to remove unreacted zinc. The filtrate was poured into 400 mlof distilled water and the oil layer was separated and dissolved indiethyl ether. The ether solution was then washed free of acid using anaqueous solution of sodium hydroxide (3%) and dried over sodium sulfate.The dried ether solution was fractionally distilled to yield 1l-perfluoroheptyl undecane-l-ol. 23.2 gm (87% yield) m.p. 50-53C.,b.p.'l40-l45C/0.4 mm Hg.

A reaction vessel equipped with a stirrer, condenser with drying tubeand thermometer, was charged with 23 gm (0.04 moles) of the product ofPart B and ml of dry pyrridine. At C., 8.3 gm of phosphorus tribromide(0.03 moles) was introduced into the reaction vessel. The reactionmixture exothermed to 40C. and was held at 3540C. by means of externalcooling. When the exotherm of the mixture subsided, infrared analysis ofthe crude reaction mixture indicated complete conversion of the alcoholto the brominated compound, (no absorption at 3.0;).

The reaction mixture was thereafter poured onto cracked ice and drownedwith 200 ml of water. The heavy oil which separated was collected,dissolved in ether and washed with water until the wash water wasneutral. The ether solution was dried over sodium sul- 8 fate, filtered,and vacuum distilled to strip the ether. The yield of purifiedl-bromo-ll-perfluoroheptyl-nundecane was 25 gm (97%).

EXAMPLE VIII This example illustrates the preparation of l-bromoll-perfluoroheptyl-10-undecene which was used as the starting materialfor a compound illustrated in Example II.

Part A:

In a suitable reaction vessel, 30 gm (approx. 0.05 mole) of crude 1l-perfluoroheptyll0-iodo-undecyll-acetate, the product of Part A,Example VII, dissolved in 30 ml of ethanol, was added at roomtemperature to a solution of 8.4 gm of potassium hydroxide in 40 ml of a3:1 mixture of ethanol and water. The resultant reaction mixture wasstirred and refluxed at 76C. for a period of 3 hours. The crudehydrolysate was thereafter poured into 400 ml of water and the oil layerwas separated and dissolved in diethyl ether. The ether solution waswashed with water until neutral and dried over sodium sulfate andfiltered. The dried ether solution was fractionally distilled to yield 1l-perfluoroheptyl-lO-undecene-l-ol, 23.9 gm (86% yield) colorlessliquid, b.p. l35140C./0.5 mm Hg. The product showed a strong absorptionat 3p.(indicating -OH) and at 6;;(indicating CI-I=CH--).

Following the identical procedure of Part C of Example VII, 19.9 gm ofthe purified 1 l-perfluoroheptyl-IO- undecene-l-ol prepared in Part A ofthis Example was converted into l-bromo-l 1-perfluoroheptyl-IO-undecene,16.1 gm (72.6% yield).

Summarizing, it is thus seen that this invention provides for thepreparation of a novel class of segmented fluorocarbon sulfonic acidsand derivatives thereof.

Variations may be made in proportions, procedures and materials withoutdeparting from the scope of this invention which is defined by thefollowing claims.

What is claimed is: l. A water and oil repellency agent consisting ofthe sulfonamides corresponding to the formula fluoropropyl-ethanesulfonamide.

3,917,691 9 10 3. A compound in accordance with claim 1: Z-p 5. Acompound in accordance with claim 1: ll-perfluoroheptyl-undecanesulfonamide.

6. A compound in accordance with claim 1: ll-perfluoroheptyll O-undecenesulfonamide.

fluoroheptyl-ethane sulfonamide.

4. A compound in accordance with claim 1: 4-perfluoroheptyl-butanesulfonamide. 5

1. A WATER AND OIL REPELLENCY AGENT CONSISTING OF THE SULFONAMIDESCORRESPONDING TO THE FORMULA
 2. A compound in accordance with claim 1:2-perfluoropropyl-ethane sulfonamide.
 3. A compound in accordance withclaim 1: 2-perfluoroheptyl-ethane sulfonamide.
 4. A compound inaccordance with claim 1: 4-perfluoroheptyl-butane sulfonamide.
 5. Acompound in accordance with claim 1: 11-perfluoroheptyl-undecanesulfonamide.
 6. A compound in accordance with claim 1:11-perfluoroheptyl-10-undecene sulfonamide.